Rails view rendering is slow in Docker - ruby-on-rails

Question

I'm dockerizing a Rails application, and I'm not sure why the views render so slow. It takes nearly 2 seconds to navigate between any two pages, with some pages taking longer. This problem does not exist when I run the application outside of Docker.
I am using Docker Desktop on a 2015 MBP with 16GB of memory.
Here is my Dockerfile:
FROM ruby:2.5.3
# replace shell with bash so we can source files
RUN rm /bin/sh && ln -s /bin/bash /bin/sh
RUN apt-get update -qq && apt-get install -y build-essential checkinstall \
libpq-dev libvips-dev libvips-tools
# python dependencies
RUN apt-get install -y libreadline-gplv2-dev libncursesw5-dev libssl-dev \
libsqlite3-dev tk-dev libgdbm-dev libc6-dev libbz2-dev
WORKDIR /tmp
RUN wget https://github.com/ArtifexSoftware/ghostpdl-downloads/releases/download/gs921/ghostscript-9.21.tar.gz && \
tar xzf ghostscript-9.21.tar.gz && cd ghostscript-9.21 && \
./configure && make && make install
RUN wget https://nodejs.org/download/release/v10.8.0/node-v10.8.0.tar.gz && \
tar xzf node-v10.8.0.tar.gz && cd node-v10.8.0 && \
./configure && make -j4 && make install
WORKDIR /app
RUN gem install bundler -v 1.17.3
RUN gem install foreman -v 0.85.0
RUN npm install -g yarn
And here is my docker-compose.yml:
version: "3"
services:
web:
build:
context: .
dockerfile: Dockerfile
command: bash -c "rm -f /app/tmp/pids/server.pid && foreman start -f Procfile.dev"
volumes:
- .:/app
- npm_packages:/app/node_modules
- bundler_gems:/usr/local/bundle/
ports:
- 3000:3000
- 8888:8888
depends_on:
- postgres
- redis
- mailcatcher
environment:
PGHOST: postgres
PGUSER: postgres
PGPASSWORD: "password"
RAILS_ENV: development
RACK_ENV: development
NODE_ENV: development
mailcatcher:
build:
context: .
dockerfile: Dockerfile
command: bash -c "gem install mailcatcher && mailcatcher --ip 0.0.0.0 --foreground"
volumes:
- .:/app
- npm_packages:/app/node_modules
- bundler_gems:/usr/local/bundle/
ports:
- 1080:1080
- 1025:1025
redis:
image: redis
ports:
- 6379
volumes:
- redis:/data
postgres:
image: postgres:9.6
ports:
- 54320:5432
restart: always
volumes:
- postgres:/var/lib/postgresql/data
environment:
POSTGRES_USER: postgres
POSTGRES_PASSWORD: "password"
volumes:
postgres:
redis:
npm_packages:
bundler_gems:
Everything works, it is just very slow.
duration=1623.74 view=1622.89

Answer 1

It could be a known problem with docker-compose running on Mac OS.
Try adding the line 127.0.0.1 localunixsocket.local to the file /etc/hosts
Found on: https://github.com/docker/compose/issues/3419#issuecomment-221793401